1. Field of the Invention
The present invention relates to buffet and serving trays and, in particular, to improvements in the chilling and heating of foods in such trays.
2. Description of Related Art and Other Considerations
Perishable foods for home, market, catering and restaurant buffets are conventionally chilled by ice or commercially manufactured containers of freezable material, or by refrigeration systems. When the ice melts and the freezable material warms, these cooling media lose their ability to maintain the foods safe and may render them unsuitable or hazardous for consumption. Refrigeration systems are bulky and costly, requiring condensers, coils and harmful chemicals and, further, must be serviced and maintained. Additionally, they are not easily adapted to be portable.
Some foods need to be heated or kept warm also for home, market, catering and restaurant buffet service. Conventional sources of heat are by flame and electricity, e.g. by use of hot plates. Flame sources many times produce local hot spots and uneven heating.
Efficiency in both cases of heating and cooling ofttimes is small, due to loss of cooling or heating to the environment; therefore, higher levels of heating and cooling input are required to maintain the desired or necessary level of temperature control.
If heated foods are to be served with chilled foods, it is customary to provide separate stations therefor, so that the heating and cooling will not interfere with one another. For very small or confined locations, the use of separate stations may be inconvenient.